There are a number of different types of wounds. Some are superficial, occurring in the first few layers of skin, while puncture wounds involve an object pushed through the skin. Wounds known as ulcers are missing a number of layers of skin, usually are cavernous, and can be found on all areas of the body. The etiology of a particular ulcer can vary greatly, and therefore such wounds have different nomenclature which is related to the diagnosis. For example, decubitus ulcers (know as bedsores) are commonly found on the sacrum, while neurotrophic ulcers have a predilection for the feet of diabetics. As the cause of an ulcer is determined, a treatment regimen and wound care of various ulcers will differ accordingly.
In treating wounds, part of the care includes an objective assessment of each wound. This evaluation includes, but is not limited to, the color, odor, temperature, condition of tissue (i.e. macerated, dry, and presence of exudate) and condition of wound dressing. If a wound is an ulcer, its size, depth and volume are of importance. It is obvious that a recorded assessment gives a treating medical practitioner a history and progress report of wound healing, which in turn is a direct reflection of a chosen treatment regimen.
Within assessment parameters, a number of methods for diagnosing and treating wounds have evolved. Patents such as U.S. Pat. No. 5,270,168 (1993) Grinnell; measures proteases to diagnose non-healing ulcers and U.S. Pat. No. 5,152,757 (1992) Eriksson; describes a chamber and system for diagnosis and treatment of wounds. Other patents concentrate on measuring a wound itself as a key factor as to how effective a treatment plan is on curing that particular wound. In the past, various methods for measuring ulcers have been employed. One such method is the utilization of a simple ruler that is placed over a wound recording its length and width. A second measurement includes the act of placing this same identical ruler in the vertical plane, which is inserted into a wound resulting in a recorded depth measurement. U.S. Pat. No. 5,749,842 (1998) Cheong & Rigby; disclose and describe a packet containing a wound dressing and a method for measuring the area of a wound.
Another method of wound assessment is to determine the volume of an ulcer by filling a tissue defect with various substances such as molding material. After filling a wound and once hardened, the molding material is then removed from a wound site and measured. An ulcer's volume in this example is equal to the volume of the hardened mold. The disadvantages of this molding method are that it is painful to a patient and disregards good sterile technique.
A less painful and less accurate method to determine volume involves filling an ulcer with fluid such as normal saline and noting the volume of fluid used.
Still another less painful and less invasive method to measure ulcer volume utilizes stereophotogrammetic instrumentation. This method requires the exact angles of two cameras focused on a wound followed by viewing and measuring the negatives to attain a particular ulcer volume.
Another U.S. Pat. No. 4,535,782 (1985) Zoltan; optically projects a visual matrix at known angles and distances into a wound allowing the volume of an ulcer to be determined.
There are numerous other patents disclosed which are used to allow assessment of wounds. Some like U.S. Pat. No. 5,265,605 (1993) Afflerbach; provide a wound assessment sheet and graph for tracing wound margins, while U.S. Pat. No. 5,702,356 (1997) Hathman; provides for a wound dressing that can be opened and resealed for the purpose of assessment and application of medication.
Further companies such as 3M, and Smith & Nephew produce transparent dressings like Tegaderm.TM. and Opsite.TM. (respectively), that provide as part of their packaging material a grid to be used to measure a wound during assessment.
Although these methods are novel for their intended purposes, they fail to provide a practitioner with vital information about a number of conditions that may occur in and around a wound site. Other aforementioned methods such as producing a mold of a wound are painful when performed and are inaccurate in measurement. Furthermore, stereophotogrammetic techniques and optically projected matrix procedures require precise measurements and angles leading to errors in calculations. Using external grids to measure open wounds or providing graphs and assessment sheets fail to give a practitioner vital information about what is occurring below a wound surface. This is true whether a wound is an open ulcer or closed superficial and or puncture wound.
The present invention provides a method and kit for examining wounds using ultrasound. This novel method provides for measuring of volumes of open wounds along with their surface area. In addition using this same method and kit allows for measuring and assessing a wound site below its surface along with the area surrounding it, both of which cannot be see by human eye. For example, assessment and measurement of an ulcer's base thickness (or floor) can be determined. Adding this novel dimension in evaluating ulcers, many of which occur over a bony prominence, will reveal if a wound is close to the surface of a bone or has penetrated a bone. Additionally, this method and kit for examination of wounds allows a practitioner to find other hidden and potential pathology that may occur below the surface of a closed wound or beyond the wall of an ulcer that cannot be seen using present methods. Tissue destruction such as a subcutaneous abscess, or a sinus tract causing lateral channeling/tunneling of a wound margin can be observed and documented. Even further, this method and kit greatly reduce the of risk cross contamination of a wound and an ultrasound transducer. This method and kit allows subcutaneous evaluation of a wound and local tissues that cannot be seen by eye from the outside surface of a wound. Finally, this method and kit unlike other testing methods, that rely on the circulation of injected dyes or radioisotopes, allows an evaluation of a wound independent of arterial or venous blood flow.